1. Field of the Invention
The present invention relates to database technologies, and more specifically to a method and apparatus for tracking modifications to values of various fields in a database server.
2. Related Art
A database server generally refers to a system which permits organization of related data and management of the organized data using structured queries. For example, in case of relational databases, SQL queries facilitate definition of schemas for tables contained in each database instance, and then to add, delete or change the data in various rows of the tables. The description is continued with respect to relational databases for illustration.
In general, the data of interest may be viewed as containing various values which are stored in fields organized in a database instance. The intersection of a column and row specifies the corresponding field in case of relational database. As may be appreciated, the values of fields can change, typically in response to queries which set the field to a new value.
There is often a need to track the modification (change) of values of several fields of interest. For example, the tracked values serve as an audit record for the corresponding field.
In the drawings, like reference numbers generally indicate identical, functionally similar, and/or structurally similar elements. The drawing in which an element first appears is indicated by the leftmost digit(s) in the corresponding reference number.